Descartes’ cosmological argument

Argument from Perfection

• 1. I have the idea of perfection within me. • 2. I am not perfect.• 3. An effect must be at least as real as its

cause. • 4. The idea of perfection has more reality than

I do, since I’m imperfect. • 5. Thus, the idea of perfection was caused by

something perfect. • 6. Thus, something perfect exists.

Argument from Infinity• 1. I have the idea of the infinite within me. • 2. I am not infinite. (I’m finite)• 3. An effect must be at least as real as its

cause. • 4. The idea of infinity has more reality

than I do, since I’m finite. • 5. Thus, the idea of the infinite was caused

by something infinite. • 6. Thus, something infinite exists.

Synthetic Propositions• Propositions whose truth value is

not determined solely by the concepts involved.

• “The predicate goes beyond the subject.” W.V.O. Quine

Examples• I have a ring on my finger.• My hair is blonde. • I have the idea of perfection within

me.• The Astros are playing well.

The argument• I am a thinking thing and I have

the idea of God.• There must be as much reality in

the cause as in the effect.• Therefore, what caused me must

be a thinking thing and have the idea of God.

The argument• Either what caused me is the cause of its own

existence or its existence is caused by another cause.• If its existence is caused by another cause, then its

cause is in turn either the cause of its own existence or its existence is caused by another cause.

• There cannot be an infinite sequence of causes.• Therefore, some cause must be the cause of its own

existence.• What is the cause of its own existence (and so,

directly or indirectly, the cause of my existence) is God.

An additional argument• Some cause is needed to keep me in

existence.• There cannot be an infinite chain of causes

because what caused me also causes my continued existence in the present.

• My parents, or any other supposed cause of my existence, do not keep me in existence.

• The only cause that could keep me in existence is God.

Objection: the causal principle

• Descartes assumes that everything has a cause. Is this true?– It is not analytic, so it is not certain – Quantum mechanics suggests some events

have no strict causes. – Ex. Radioactive decay, maybe some gasses

(Poincare’s Conjecture), etc.

Bad Start, Good Finish Objection

“My view of perfection is different from yours.”•Suppose something which neither of

us can think of satisfies both our views of perfection. Then, we do have the idea of perfection; it’s just not quite right.

•Does Descartes need our idea of perfection to be perfect?